Remove last usage functions from HostContentSettingsMap and clean up prefs

chrome/browser/notifications/platform_notification_service_impl.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/notifications/platform_notification_service_impl.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/metrics/histogram_macros.h"
@@ skipping 301 matching lines @@
 #if defined(OS_WIN)
     std::string profile_id =
         base::WideToUTF8(profile->GetPath().BaseName().value());
 #elif defined(OS_POSIX)
     std::string profile_id = profile->GetPath().BaseName().value();
 #endif
     *cancel_callback =
         base::Bind(&CancelNotification, notification.delegate_id(), profile_id,
                    profile->IsOffTheRecord());
   }
-
-  HostContentSettingsMapFactory::GetForProfile(profile)->UpdateLastUsage(
-      origin, origin, CONTENT_SETTINGS_TYPE_NOTIFICATIONS);
 }
 
 void PlatformNotificationServiceImpl::DisplayPersistentNotification(
     BrowserContext* browser_context,
     const std::string& notification_id,
     const GURL& service_worker_scope,
     const GURL& origin,
     const content::PlatformNotificationData& notification_data,
     const content::NotificationResources& notification_resources) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
@@ skipping 14 matching lines @@
       browser_context, notification_id, origin, settings_button_index);
 
   Notification notification = CreateNotificationFromData(
       profile, service_worker_scope, origin, notification_data,
       notification_resources, delegate);
 
   GetNotificationDisplayService(profile)->Display(
       NotificationCommon::PERSISTENT, notification_id, notification);
   content::RecordAction(
       base::UserMetricsAction("Notifications.Persistent.Shown"));
-
-  HostContentSettingsMapFactory::GetForProfile(profile)->UpdateLastUsage(
-      origin, origin, CONTENT_SETTINGS_TYPE_NOTIFICATIONS);
 }
 
 void PlatformNotificationServiceImpl::ClosePersistentNotification(
     BrowserContext* browser_context,
     const std::string& notification_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   Profile* profile = Profile::FromBrowserContext(browser_context);
   DCHECK(profile);
 
@@ skipping 146 matching lines @@
   }
 #endif
 
   return base::string16();
 }
 
 void PlatformNotificationServiceImpl::SetNotificationDisplayServiceForTesting(
     NotificationDisplayService* display_service) {
   test_display_service_ = display_service;
 }